1. Field of the Invention
The present invention relates to an integrating meter and, more particularly, to an integrating meter installed in vehicles and adapted to totalize the distance traveled thereby.
2. Description of the Prior Art
One representative type of conventional integrating meter comprises an enclosure containing a shaft that supports thereon a plurality of rotatable number rings arranged side by side. The number rings re equipped with pinion gears therebetween. The pinion gears are driven to produce shifts from less to more significant digits of the rings so that the rings when aligned indicate the result of integrating operations.
FIG. 3 is a top view of one such prior art integrating meter for use on vehicles. In the rear of a dial 1 that provides the front of the meter enclosure is a frame 3 mounted on a chassis 2. Attached to the frame 3 is a support shaft 4 that has a plurality of rotatable number rings 5 mounted thereon and arranged side by side. To the right of the least significant digit number ring 5 is a transmission gear 8, a driving gear 6 and a reduction gear 7, the latter two gears being rotated by a predetermined driving force. The driving force transmitted to the least significant digit number ring 5 via the transmission gear 8 is in turn conveyed to more significant digit number rings via pinion gears, not shown, to provide necessary shifts in numeral data represented by the rings.
To the left of the most significant digit number ring 5 is a blank rotatable ring 9 for masking purposes. Between the ring 9 and the frame 3 are the number rings 5 aligned within a display window 10 formed on the dial 1. A coil spring 11 is provided to push the rings 5 in the thrust direction. This construction is intended to ensure some room for movement of the rings in the thrust direction.
In the integrating meter of the above-described construction, the coil spring 11 ensures an easy-to-view numeric display by definitely aligning the number rings 5 within the window 10 of the dial 1. The rotatable ring 9 to the left of the most significant digit number ring 5 prevents any gap from developing between the side of that ring and the edge of the display window 10. Installed where it is, the ring 9 shields the view of the internal mechanisms of the integrating meter from outside and keeps the internal lighting for nighttime illumination from leaking out of the enclosure.
One disadvantage of the above conventional integrating meter is the need to mount the coil spring 11 on the support shaft 4 so as to push the number rings 5 and the rotatable ring 9 in the thrust direction, all the rings being rotatably supported by the shaft. Being a discrete part, the coil spring 11 increases the total number of meter parts and requires another process in which to mount it onto the support shaft 4. As a result of this, production cost is increased with the prior art.